An ice slurry can be used for cooling, for example in the manufacture of concrete or in mining. Making ice in a vacuum is known and used, inter alia, for desalination of sea water. In, for example, U.S. Pat. No. 1,976,204 and U.S. Pat. No. 3,202,343, the manufacture of ice in a vacuum is described. In DK B No. 147 833 a method and a device for the manufacture of ice in loose form are described, in which vapour from a vacuum vessel containing water is sucked off by means of a vapour compressor. The vapour is then compressed to a preset pressure to enable condensing on a cold surface without freezing occurring. A water vapour compressor is comparatively too expensive to be used in these applications.